The aim of this project is to study the functional anatomical organization of neurons of the visual system of non-human primates that can serve as a model for the human visual system. Parcellation of the monkey visual cortex is based on silver cell, silver myelin and cytochrome oxidase staining and on connectional studies. Cytochrome oxidase staining is also being used to activity label chronic stimulation states in the brain, and improvements in the 2-deoxyglucose activity labeling method for acute stimulation states are being developed. Retinal studies have focused on blue-sensitive cones, their pattern and synaptology and the mechanism by which blue-sensitive cones may be specifically stained.